Capacity-controlled electronic coin totalizer



Sept. 23, 1958 J. F. MORRISON 2,853,173

CAPACITY-CONTROLLED ELECTRONIC com TOTALI'ZER FiledMay 12, 195s TTOP/VEY United States Patent Gliice 2,853,173 Patented Sept. 23, 1958 CAPACITY-CONTROLLED ELECTRONIC COIN TOTALIZER John F. Morrison, Boonton, N. J., assigner to Rowe Manufacturing Co., Inc., Whippany, N. J., a corporation of New York Application May 12, 1953, Serial No. 354,522 2 Claims. (Cl. 194-10) My invention relates to a capacity-controlled electronic coin totalizer and more particularly to Ian electronic totalizer for use with vending machines.

It is desirable in vending machines to sell merchandise in response to the deposit of a plurality of coins of diierent denominations whose value will equal the price of the merchandise being sold. For example, if cigarettes are to be sold at twenty-live cents per pack through merchandising machines, it is advantageous that a purchaser be able to operate the machine in response to the deposit of a quarter, a dime and three nickels, two dimes and a nickel, or tive nickles. Furthermore, it is useful that a merchandising machine be able to give change in event that coins greater in value than the price of the merchandise be deposited. For example, if a candy bar sells for fteen cents, it is of advantage that a merchandising machine operate for three nickels, or Ia dime and a nickel, and further, to operate in response to the deposit of two dimes so that both the merchandise and `a nickel in change be given, or in response to a quarter in which case the merchandise and two nickels in change will be given. p

There are many devices in the prior art adapted to operate vending machines in response to coins of a plurality of different denominations. Some of these devices are mechanical and some are electrical. In the electrical devices a plurality of relay switches have been used 'adapted to set up the vending circuit. In othercases a combination of an electrical and mechanical means has been employed.v All of the devices of the prior' art are expensive to construct and relatively inexible in their operation. v

One object of my invention is to provide an electronic totalizer circuit which is llexible in that it can handle a wide variety of coins.

Another object of my invention is to provide a capacitor-type totalizer circuit in which the price at which the merchandise is to be sold .can be varied within wide limits in a simple, convenient and expeditious manner.

Another object of my invention is to provide a capacitor-type totalizer which is inexpensive to construct and certain in operation. A

A further object of my invention is to provide a capacitor-type totalizer circuit adapted to operate a vending machine in response to the deposit of a plurality of coins aggregating the price of the merchandise .or more and in event coins greater in value than the price of the merchandise are deposited, to give change for the difference represented between the amount deposited and the value of the merchandise.

Other and further objects of my invention will appear from the following description.

The accompanying drawing which forms part of the instant specication and which is to be read in conjunction therewith is a diagrammatic view lof a Vcapacitor-type totalizer circuit forming one embodiment of my invention;

In general my invention'contemples the provision Vof a thyratron having a gn'd circuit comprising a plurality of capacitors connected in parallel. One of the capacitors has a capacity equivalent to a desired effect upon the deposit of a nickel. Another capacitor has a larger capacity to create the desired voltage increment to be occasioned by the deposit of a dime. A third capacitor has a still larger capacity adapted to create a voltage increment equivalent to the deposit of twenty-tive cents. The three coin capacitors are normally connected across a source of direct current potential and allowed to be charged. Coin switches adapted to disconnect each of the coin capacitors upon the deposit of a coin and to place the corresponding coin capacitor in parallel with a storage capacitor are provided. The output of the storage capacitor is connected to the grid of a thyratron. i

'first thyratron will initiate the Vending cycle and the firing of the second thyratron will initiate the change-making cycle. The delivery of merchandise will serve to discharge the storage capacitor and place it in condition for another cycle of operation.

More particularly referring now to the drawing, a source of direct current potential between and 300 volts is placed across terminal 10 and ground 12. A voltage regulator comprising a pair of space-discharge tubes 14 and 16 serve to maintain the voltage between terminal 18 and ground at a predetermined point. A current-limiting resistor 20 is placed on the line to prevent surges of current. The conductor 22 is thus maintained at asteady potential say of 300 Volts. This conductor communicates with terminals 24, 26 and 28 through conductor 30. Coin-actuated switch 32 is normally in contact with contact 24; lcoin-actuated switch 34 is normally in contact with contact 26; and coin-actuated switch 36 is normally in contact with contact 28. In this manner the line voltage is impressed across capacitor 38, capacitor 40 and capacitor 42, the other sides of these capacitors being connected to the ground conductor 44. Each of the capacitors 38, 40 and 42 will be charged to the line voltage. The resistors 46, 48 and 50, placed in series with the respective capacitors 38, 40 and 42, are current-limiting resistors adapted to prevent peaks or surges. The switch 32 is adapted to Vbe operated byV a nickel and the capacitor 38 may advantageously have a capacity of .2 microfarad. The switch 34 is adapted to be actuated by a dime and the capacitor 40 may have a capacitance of .42 microfarad. Y The switch 36 is adapted to be actuated by a quarter and the capacitor 42 may have a capacitance of 1.0 microfarad.

A capacitor 52 and a capacitor 54 are connected inl parallel with each other through a resistor 56 and across ground 44 and conductor 58. Contacts 60, 62 and 64 are connected to conductor 58. Upon the actuation of the coin-controlled switches each oneis adapted selectively to connect its corresponding capacitor in parallel with the capacitors 52 and 54. For example, when the nickel switch arm 32 is operated, the capacitor 38` is placed in parallel with the capacitors 52 and 54 through contact 64. For purposes of convenience, I shall refer to thecapacitors 52 and 54 asV the storage capacitors and capacitors 38, 40 and 42 as coin capacitors. In a similar manner the coin capacitor 40 may be placed in parallel with the storage capacitors when switch arm 34 contacts contact 62. .Likewise,V upon the actuation of switch arm 36 by a quarter the quarter capacitor 42 is placed in parallel with the coin capacitors through contact 60. The storage capacitors are connected by conductor 66 to the control grid 68` of a thyratron 70. A

` resistor 72'is placed in the conducting channel 66 to pre-4 vent current surges. A resistor 74 having a very high resistance is shunted across the storage capacitors to insure a complete discharge of any residual voltage in the storage capacitors in order to preclude the danger of the thyratron tiring before coins of the desired value have been placed in a coin device (not shown) to trip the coin-actuated switches.

There are many coin devices equipped with slug ejectors to eject spurious coins adapted to actuate microswitches by the passage of coins therethrough. Since these coin registers form no part of this invention and they are well known to the art they are not described. It is sufficient for the purpose of this invention that a switch is provided which, in response to the deposit of a coin, will break one contact and make another. The coin register separates nickels, dimes and quarters besides ejecting spurious coins. The separated coins are passed to corresponding runways or channels in which a switch-operating member, such as a fine wire, is positioned.

For purposes of illustration, let us assume that we have determined that the characteristics of the thyratron 70 are such that a voltage differential of two volts should iire it for a purchase. With this hypothesis we will need a voltage differential of one-half volt for a nickel, one volt for a dime and two and one-half volts for a quarter. As is known in the art the capacitance of capacitors connected in parallel adds algebraically. I select the capacities of the respective storage capacitors 52 and 54 to have a total capacitance of l2() microfarads. Considering now the nickel capacitor 38, which we have constructed with a capacitance of .2 microfarad, this capacitor is fully charged to three hundred volts due to the fact that it is placed directly across the line by switch arm 22 and contact 24. Upon the actuation of the switch 32 by a nickel the capacitor 38 is placed in parallel with the storage capacitors and the voltage in all three capacitors is equalized. Using the well-known electrical formula Q=CE, with the capacitances indicated above and a line voltage of three hundred volts, we see that the effect of one nickel is to charge the storage capacitors to a voltage of .499 volt, or approximately one-half volt. In a similar manner, the deposit of a dime will charge the storage capacitors with a voltage of 1.05 volts, while the deposit of a quarter will charge the storage capacitors to a voltage of 2.47 volts. In other words, for the capacitance of the capacitors chosen we obtain approximately one-half volt increment in the storage capacitors for each tive-cent value of the coin placed in the coin register.

The plate 76 of the thyratron 70 is connected by conduetor 78, switch arm 80 and conductor 82 to theV three hundred-volt positive terminal 18. The switch arm 80 forms one arm of a gang switch 83 having switch arms 84 and 86 adapted to be operated simultaneously. The switch arm 80 is normally in contact with contact 90. The switch arm 84 is normally out of contact with contact 92 and the switch arm 86 is normally out of contact with the contact 94. A cam 91 carried by a shaft 93 adapted to be rotated by the operation of the vending machine, as is well known in the art, is adapted to operate the cam switch 88 to break the contact with contact 90 and to make contact, respectively, between switch arm 84 and contact 92 and switch arm 86 and contact 94. It will be observed that both switch arms 84 and 86 are connected to ground by conductor 96. Contact 94 is connected by conductor 98 to the positive side of the storage capacitor 52 and contact 92 is connected by conductor 100 to the positive side of storage capacitor 54. The arrangement is such that upon the actuation of the switch 88 the plate voltage is disconnected trom the plate 76 of the thyratron and the storage capacitors are discharged by direct connection to ground.

The screen grid 102 of the thyratron 70 is connected to ground by conductor 104. The cathode 106 is con- 4 nected to a potentiometer 108 which is placed across the high-voltage line by means of conductor 110. The variable arm 112 of the potentiometer is connected by conductor 114 to the cathode 106 and determines the cathode bias. The left-hand branch of the potentiometer 108 is paralleled by two variable .resistors 116 and 11S adapted to be connected in parallel with the left-hand arm of the potentiometer 108 by push-button switches 120 and 122, respectively, through conductor 124. Advantageously push button 120 may, for example, be associated with a column of merchandise in a vending machine adapted to vend for twenty cents. Push button 122 is adapted to be associated with a column of merchandise adapted to vend for twenty-tive cents. The effect of placing the resistors 116 and 118 in parallel with the left-hand branch of the potentiometer 108 is to reduce the positive bias upon the cathode 106, performing the same function as moving the arm 112 of the potentiometer 108 to the left. The adjustment of the variable resistance 116 is such that the thyratron will tire when about two volts positive potential is placed upon the control grid 68. The adjustment of variable resistor 118 is such that the thyratron 70 will tire when about two and one-half volts is placed upon the control grid 68. At voltages below this the thyratron will not ire. When the thyratron fires, current willl flow through the relay winding 126 to close the relay contacts 128 to energize the vending motor and initiate the vending cycle of the vending machine. A current-limiting resistor 130 is placed in the line supplying voltage to the plate 76. A second thyratron 132 is provided to control the changemaking device. This is operated whenever current tlows through the second thyratron to energize the relay winding 134 to close relay contacts 136. Whenever this occurs the change-maker is operated to give appropriate change, say, for example, a nickel. It will be observed that the thyratron 132 has a control grid 168 connected in parallel with the grid 68 of the thyratron 70. Similarly, the plate 176 is in parallel with the plate 76 of the thyratron 70. The screen grid 202 is placed at ground potential. The cathode 206 is biased from a potentiometer 208, connected across the 30G-Volt line, by means of a variable arm 212. A variable resistor 216 is adapted to be placed in parallel with the left-hand branch of the potentiometer '208 whenever push button 120 is operated. The adjustment of the resistance of the resistor 216 is such that it will re at twenty-five cents, that is, when a voltage equivalent to twenty-tive cents, or in this case, of two and one-half volts, is placed upon the control grid, but will not fire at a voltage less than this on the control grid 168. It will be clear that if a quarter is deposited, a voltage more than suicient to re the thyratron 70 is impressed upon the control grid 68 and a voltage suicient to tire the thyratron 132 will be irnpressed upon the control grid 168 if the push button 120 is operated. Accordingly, the user of the machine will obtain the merchandise through the operation of the vending cycle and will receive a nickel iu change if a quarter is deposited. If the push button 122 is pressed, however, to operate another column of the vending machine containing articles adapted to vend for a quarter, the presence of lsuliicient voltage upon the control grid 168 will not lire the thyratron 132 due to the increased positive bias upon the cathode 206 which will not be lowered since push button 120 has not been operated. In this manner change will be given only upon the operation of the lower-priced column but not for the higherpriced column. If, however, three dimes are deposited, sutlicient voltage is automatically impressed upon the control grid 168 so that change of a nickel will be given for three dimes and a 25 item can be obtained by operating the push button 122. If the purchaser should foolishly deposit three dimes to obtain a 20 item he will automatically lose a nickel.

It will be understood, of course, that the coin values -.given above are illustrative only and by .adjusting the potentiometenllZ and the variable resistors 116 and 118 my totalizer can be set to operate the vending cycle for any aggregate valueof `coins within reasonable limits. With a 300-voltline voltage, for example, we can, theo-` retically, have an upper limit of $6.00 with the values of the capacitors shown. By-making the value of the coin capacitors smaller we can increase the upper limit to a greater value, although this is seldom necessary or desirable in a vending machine. Similarly, it will be recognized by those skilled in the art that one of the coin switches may be made to operate for a penny and a capacitor having a capacitance of .04 microfarad may be placed in parallel-with the coin capacitors and provit-led with a switch similar to switch 32 to voperate for a penny. The value in money at which the thyratron will re can be very readily `and expeditiously adjusted by means-of `the potentiometer 112 and the variable resistors 116 and 118. By placing additional push button-controlled resistors similar to resistors 116 and 118 in parallel with these resistors we can have a plurality of columns each adapted to vend merchandise at a different price.

The operation of my totalizer will be described, for purposes of convenience, with two columns set to operate at twenty cents and twenty-five cents and to give change of a nickel with the deposit of a quarter on a 20 purchase.

Let us assume that a 20 purchase is to be made. The purchaser may deposit four nickels, in which case the storage capacitors will be charged to approximately two volts in successive increments of one-half volt by the successive deposits of nickels. When the push button 120 is pressed, the cathode bias is so adjusted that the voltage on the control grid 68 of two volts will be suicient to tire the thyratron 70 and initiate the vending cycle. The voltage occasioned by the deposit of four nickels will be insuiicient to fire thyratron 132 so that no change will be given on a 20 purchase with four nickels. The twenty cents may be achieved by the deposit of two nickels and a dime, the storage capacitors being charged to the same voltage by the successive operation of the nickel coin capacitor and the dime coin capacitor 40. The twenty cents may be attained by the deposit of two dimes. In this case the capacitor is placed in parallel with the storage capacitors twice and successively charges them to approximately two volts. The 20 purchase may likewise be effected by means of the deposit of a quarter. In this case the storage capacitors are charged to a voltage of approximately two and one-.half volts. This is suliicient not only to tire the thyratron 70 upon the actuation of push button 120 but is also suflcient to fire the changemaking thyratron 132 so that a purchaser will receive the merchandise from the vending machine with which my totalizer is associated and a nickel in change. The twenty-cent charge of approximately two volts will be insulicient to re the thyratron if the quarter push button 122 is pressed. It will be necessary, to make a quarter purchase, to deposit an additional nickel if only coins aggregating twenty cents have been deposited. It is possible to deposit three dimes to achieve a charge sufficient to fire the thyratron by the 25 push button 122. In this case there will be a voltage of approximately three volts upon the control grids 68 and 168. The adjustment of the cathode bias of the cathode 206 by means of the potentiometer 208 and its associated arm 212 is such that the thyratron 132 will re when three volts have been .placed upon the control grid 168. Accordingly, upon the deposit of three dimes, a nickel in change is automatically given by the change-maker. The thyratron 70, however, will not ire when three volts are placed upon the control grid 68. It requires an alteration in the cathode bias by means of the column-controlling push button. The pressing of either push button 120 or 122 will cause the vending thyratron to tire when this state exists, that' is, when coins totaling thirty cents have been deposited. in the totalizer. Normally, the quarter push button will be pushed after three dimes have been deposited.

It will be seen that I have accomplished the objects of my invention. ,I have provided a exible capacitor-type totalizer circuit adapted to control a vending machine to vend at any desired price within the limits of the capacitors and voltages involved. The price at which my totalizer circuit will operate may be altered rapidly and expeditiously and adjustment can be made very simply if it is desired to set the machine for a particular price by depositing coins equalling this price to place a corresponding charge upon the storage capacitors. The bias of the cathode of the thyratron has previously been set suiciently high to prevent it from ring. 'With the charge in the storage capacitors the bias is reduced until the thyratron lires. This bias can be reduced by pressing the push button and reducing the resistance of the parallel variable resistor 116 or 118. After this has been done it will be found that the thyratron will re automatically upon the deposit of the requisate number of coins to which it has been set. The exibility of my totalizer will be apparent from the foregoing description. Every time the thyratron iires, the vending cycle will operate and the operation of the vending cycle will automatically discharge the storage capacitors. The shunting resistor 74 prevents the accumulative building up of charges in the storage capacitors. Its resistance is so high that within the time period involved during the Vending cycle sufiicient voltage will not leak 01T to affect the tiring of the thyratron. Once the thyratron has lired and its gas has ionized, it will continue'to conduct until the vending cycle is completed, at which time the plate circuit is interrupted by the opening of the switch arm 80.

It Will be understood that certain features and subcombinations are of utility and may be employed without reference to other features and subcombinations. This is contemplated by and is within the scope of my claims. It is further obvious that various changes may be made in details within the'scope of my claims without departing from the spirit of my invention. It is therefore to be understood that my invention is not to be limited to the specific details shown and described.

Having thus -described my invention, what I claim is:

1. In a capacity-controlled electronic coin totalizer for merchandising machines, a thyratron having a control grid and a cathode, a rst coin capacitor normally connected across the potential source, a second coin capacitor having a capacity substantially a multiple of the capacity of the first capacitor connected across the potential source in parallel with the first capacitor, a storage capacitor having one side thereof normally connected to one side of each of the coin capacitors and the other side thereof connected to the control grid, a first coinoperated switch adapted to be operated by a coin of a iirst denomination and adapted to disconnect the rst coin capacitor from the potential source and to place it in parallel with the storage capacitor, a second coin-operated switch adapted to be operated by a coin of a second denomination and adapted to disconnect the second coin capacitor from the potential source and to place it in parallel with the storage capacitor and means for placing a predetermined bias on the cathode, the construction being such that when the storage capacitor becomes charged to a predetermined voltage the thyratron will lire.

2. In a capacity-controlled electronic coin totalizer for a merchandising machine having a rst switch adapted to be actuated to initiate a vending cycle and a second switch adapted to be actuated to give change, a thyratron having a control grid and a cathode and a plate circuit, a first relay winding connected in said iirst thyratron plate circuit and adapted to be energized to actuate said first switch, a second thyratron having a control grid and a cathode and a plate circuit, a second relay winding connected in said second thyratron plate circuit and adapted to be energized to actuate said second switch, a source of direct current potential, a coin capacitor normally connected across the potential source, a storage capacitor having one side thereof normally connected to one side of the coin capacitor and the other side thereof connected to the respective control grids, a coin-operated switch adapted to disconnect the coin capacitor from the potential source and to place it in parallel with the storage capacitor, means for placing a predetermined bias on the cathode of the first thyratron, means for placing a predetermined bias higher than that on the first thyratron upon the second thyratron, the construction being such that when the storage capacitor becomes charged to a first predetermined voltage the first thyratron will fire to energize said first winding to actuate said first switch to initiate `a vending cycle but the second will not and when the storage capacitor becomes charged in excess of a second predetermined voltage both thyratrons will re to energize said first and second windings to actuate said first switch and said second switch to initiate a vending cycle and to give change.

References Cited in the file of this patent UNITED STATES PATENTS 

